GitLab

e1482394

by Simon Peyton Jones at 2025-05-14T23:21:36-04:00

Improvements

esp inline top level things not-under-lambda only if it's a function.
Beware extra iterations in T18698a

@@ -1124,7 +1124,7 @@ mkNonRecRhsCtxt lvl bndr unf
          -- Distressing delicacy ... has to line up with preInlineUnconditionally
          case idOccInfo bndr of
            OneOcc { occ_in_lam = NotInsideLam, occ_n_br = 1 }
 -            -> active && not (isTopLevel lvl) && not stable_unf
 +            -> active && not stable_unf
            _ -> False
      active     = isAlwaysActive (idInlineActivation bndr)

@@ -1465,7 +1465,7 @@ preInlineUnconditionally env top_lvl bndr rhs rhs_env
                    , occ_in_lam  = NotInsideLam
                    , occ_int_cxt = int_cxt }
        =  isNotTopLevel top_lvl      -- Get rid of allocation
 -      || (int_cxt==IsInteresting)   -- Function is applied
 +      || (int_cxt==IsInteresting && idArity bndr > 0)   -- Function is applied
     --   || (early_phase && not (isConLikeUnfolding unf))  -- See early_phase
      one_occ OneOcc{ occ_n_br   = 1
                    , occ_in_lam = IsInsideLam
@@ -1632,6 +1632,7 @@ postInlineUnconditionally env bind_cxt old_bndr bndr rhs
      unfolding   = idUnfolding bndr
  --    arity       = idArity bndr
      is_cheap    = isCheapUnfolding unfolding
 +    is_exp      = isExpandableUnfolding unfolding
      uf_opts     = seUnfoldingOpts env
      phase       = sePhase env
      active      = isActive phase (idInlineActivation bndr)
@@ -1639,6 +1640,8 @@ postInlineUnconditionally env bind_cxt old_bndr bndr rhs
      -- Check for code-size blow-up from inlining in multiple places
      code_dup_ok n_br
 +      | is_top_lvl          -- Don't inline top-level datacons, ever; no advantage,
 +      , is_exp      = False -- and float-out may have carefully created them
        | n_br == 1   = True  -- No duplication
        | n_br >= 100 = False -- See #23627
        | is_demanded = False -- Demanded => no allocation (it'll be a case expression